John Stamos realized rather quickly that Mary-Kate Olsen and Ashley Olsen were simply two of a kind.
 
However, the Full House alum—who released his memoir If You Would Have Told Me on Oct. 24—admits he wasn't completely sold on working with the scene-stealing twins at first when they landed the part of the adorable but sassy Michelle Tanner. In fact, he recalls in vivid detail getting them temporarily fired during their early days on the show.
 
"I'm trying to get through a scene, and the cutesy twins are crying their heads off," he writes, "They'd rather be anywhere in the world other than that set, and I'm right there with them."
 
But after briefly working with another pair of "homely as hell" twins, John had the Olsens back on set in a New York minute—and the rest would be eight-seasons-long history.
 
"I'm spending more off-camera time with Mary-Kate and Ashley," the General Hospital alum adds, "I adore them, and they adore me."

And though most of the Tanner clan would reunite for the 2016 sequel series Fuller House, the Olsen twins, who stepped back from acting more than a decade ago, decided not to reprise their shared role. And while John previously admitted to being "angry" at first with their choice, he still looks back at the show—and his bond with the twins—as a life-changing experience.
 
"Full House is the kind of hit that comes along once in a lifetime if you're lucky," the You actor writes in his book, "I'm not talking about big ratings, lots of dough, or the way it becomes part of pop culture. It's more than a show, it's a family. It's everyone's family."

As for everything you want to know about the adorable twins from that family? Keep reading to find out everything John shared in his new memoir.

As John Stamos reveals in If You Would Have Told Me, the twins were the final ones to be cast in the Full House family.

"The last casting call is for Danny's littlest daughter,” he notes, “Two adorable munchkins, Mary-Kate and Ashley Olsen, are cast in the role of Michelle. They have big blue eyes wide with wonder. As identical twins, they can take turns sharing short takes without spending long hours on the set.”

Little did he know just how influential Michelle Tanner would prove to be.

"I'm thinking they've put a lot of work into casting these kids who are just going to be in the background,” he noted, before praising the series creator, “but I admire Jeff [Franklin] for his attention to detail. Good for him."

It wasn’t always smooth sailing for Uncle Jesse when it came to working with the twins at first, who were just six months old when they were cast in 1987. In fact, one day, the dynamic came to a screeching halt.

"I'm trying to get through a scene, and the cutesy twins are crying their heads off,” he writes, “They'd rather be anywhere in the world other than that set, and I'm right there with them."

And this would lead John to deliver an ultimatum to the show’s crew.

"‘It's either me or them,” the ER alum continues, “’They're not going to work out. They'll ruin this show and my career.'”

But John himself notes, "Be careful what you wish for.”

“When you get your way in Hollywood, there's usually a catch. I send the Olsens and their diaper bags packing, and a new set of perfectly behaved twins are paraded onto the set. They are quiet, calm, and homely as hell. I know, I'm one to talk. For the longest time, the neighbors thought my parents got a pet monkey. But here's the difference: I wasn't trying to be in show business yet.”

Needless to say, John requested that the twins (and the diaper bags) come back to set immediately.  

“’Jeff, could we please bring back the Olsen twins?’ I say sheepishly,” he recalls. “I may have misjudged the situation. It turns out that Jeff didn't allow them to go too far, they were actually waiting backstage."

Not only did John begin to bond with the sisters on-set, but as the You actor revealed, they ultimately had a huge impact on the way he envisioned himself as a dad.

"I'm spending more off-camera time with Mary-Kate and Ashley,” he explains, “I adore them, and they adore me. Writers start developing more Jesse and Michelle stories, which become a highlight of the show. We have it down to a science; Mary-Kate is stronger in the emotional scenes, Ashley scores in the comedic ones."

He adds, "I'm starting to really love the scenes with the Olsen twins. Right away, I know the relationship between Jesse and Michelle is an important one, but as the show develops, the connection grows.”

And so does his outlook on his life.

"I'm young, but I want kids someday,” John, who was around 24 years old when he landed the part, continues, “and these lovely little girls, so bouncy and bright, represent the best versions of future dreams. They allow me to consider fatherhood like a benched baseball catcher in a dugout, watching from afar without having to catch any curveballs.”

As he put it, "I take them to Disneyland, I adore them, give 'em kisses on the tops of their heads, buy them a few crappy souvenirs, and then hand them back to their parents to do the hard work.”

It turns out Mary-Kate and Ashley weren't the only family members to forge a bond with John, as younger sister Elizabeth Olsen would also pop onto the set.

"Their little sister, Lizzy, comes to visit them on the set, and she quickly becomes my new favorite Olsen," he explains, "Not knowing, of course, that one day in the future the two of us would both have places in the Marvel Universe (her Scarlet Witch being a little more prominent than the Iron Man voice I do on Disney Plus's Spidey and His Amazing Friends)."

When the General Hospital alum wed Rebecca Romijn in 1998, most of the Full House family, including the twins, were front and center to witness the nuptials.

“Inside at the reception, there are elegant Amazons from her world, Heidi Klum and Tyra Banks, and Rebecca’s Dutch relatives, each taller than the next, eclipsing the models,” he recalled of the event for the couple, who split in 2004. “The Full House family—Candace [Cameron Bure], Mary-Kate, Ashley, and Lori [Loughlin], Bob [Saget], and Dave [Coulier]—all show up to support me.” 

Seven years after Full House came to an end in 1995, John found himself shifting gears and hit the Broadway stage, starring as the Emcee in the Tony-winning revival of Cabaret in 2002. And by then he notes, the Olsen twins were making waves beyond the TV screen as their budding fashion careers were taking off.

“The Olsen twins are all grown up and have moved to NYC to begin building their multimillion-dollar fashion and entertainment businesses,” he writes, “It’s pretty weird having adult Michelles sitting there in stereo watching me play someone so different from their beloved Uncle Jesse, but they get it. We share a mutual pride for how far we’ve all come.”

John shared that his relationship with costar Bob grew increasingly close over the years, especially after their respective splits. (Bob and ex Sherri Kramer broke up in 1997, the same year John and Rebecca—who divorced in 2004—got engaged.)

“Bob and I are now both single and we’re spending a lot more time together as well,” he recalls, “Our relationship is shifting from being good friends to being the brothers we both wished we had.”

And as patriarch of the family, Bob took his role on-and-off very seriously, making sure the Full House family—both in front of and behind the camera—were included in that tight bond.

"Bob rallies the Full House crew to come hang,” John reveals. “He makes sure we all stay close. He knows how important it will turn out to be. I can't think of one sitcom where the cast is closer than family, supports each other, and spends an embarrassing amount of time together like ours. Bob is the glue."

In fact, John recalls one instance where he made sure at least one of the twins evaded photographers after a hangout.

“In the morning, Bob sneaks one of the Olsen twins down to the beach and into a waiting car to avoid the paparazzi,” he shares, “He still feels like a father figure to the girls, no matter how old or rich they become.”

Despite any bumps in the road that may developed over time, (i.e., when Ashley and Mary-Kate decided to not return for Fuller House), when Bob passed away in January 2022, the costars leaned on each other for endless support in real-life. 

“His death brings a well-deserved tsunami of love, an outpouring from all ages, respect from his peers,” John notes, “What a talent. What a kind, good man. What an icon. These are the accolades he wanted all his life. The irony is, he already had it.”